Machines for removing worn road surfaces

ABSTRACT

APPARATUS FOR REMOVING A WORN ROAD SURFACE DOWN TO A PREDETERMINED, DEPTH PRIOR TO THE APPLICATION OF A NEW SURFACE, COMPRISES A CHASSIS SUPPORT MEANS FOR THE CHASSIS IN THE FORM OF ROAD WHEELS OR TRACKS MEANS TO DISPLACE SAID CHASSIS IN A FORWARD AND/OR REVERSE DIRECTION, A PICK-CARRYING HYDRAYLICALLY DRIVEN CUTTING DRUM SUPPORTED FROM SAID CHASSIS AND LOCATED WITHIN SAID SUPPORT MEANS THEREOF AND ROTATABLE IN THE SAME DIRECTION AS THE ROAD WHEELS ABOUT A HORIZONTAL AXIS AT AN ANGLE TO THE LONGITUDINAL AXIS OF SAID CHASSIS, AND MEANS TO ADJUST SAID CUTTING DEVICE IN A SUBSTANTIALLY VERTICAL PLANE TO DETERMINE THE DEPTH OF SAID ROAD SURFACE TO BE REMOVED.

Feb. 2, 1971 P. LOCKWOOD MACHINES FOR REMOVING WORN ROAD SURFACES 2Sheets-Sheet 1 Filed Feb. 24, 1969 mule/v TOP [Ere/e Lac/(0000 8)56%750/7 60 5 a/e/xvm E W a/ M S Feb. 2, 1971 v P. Loc wooo 3,560,050

MACHINES FOR REMOVING WORN ROAD SURFACES Filed Feb. 24, 1969 2Sheets-Sheet 2 BY k/MBWW do: G l/N 006 me 406 7344 WW Y5 United StatesPatent 3,560,050 MACHINES FOR REMOVING WORN ROAD SURFACES PeterLockwood, Darlington, England, assignor t Greenside Machine CompanyLimited Filed Feb. 24, 1969, Ser. No. 801,548 Claims priority,application Great Britain, Mar. 20, 1968, 13,430/68; July 16, 1968,33,811/68 Int. Cl. E01c 23/09 US. Cl. 299-39 5 Claims ABSTRACT OF THEDISCLOSURE Apparatus for removing a worn road surface down to apredetermined depth prior to the application of a new surface, comprisesa chassis support means for the chassis in the form of road wheels ortracks means to displace said chassis in a forward and/ or reversedirection, a pick-carrying hydraulically driven cutting drum supportedfrom said chassis and located Within said support means thereof androtatable in the same direction as the road wheels about a horizontalaxis at an angle to the longitudinal axis of said chassis, and means toadjust said cutting device in a substantially vertical plane todetermine the depth of said road surface to be removed.

This invention relates to road working machines and in particular tomachines adapted to operate on the surface of a road prior tore-surfacing.

It is customary to apply heat to a road surface for removing the Wornasphalt or macadam surface therefrom, before employing a means fordetaching a usually threeinch thickness of the softened road material soas to ensure thereby satisfactory application of a new surface. Suchapparatus is usually complex. necessitating the transport of a machinecontaining fuel with burners to direct heat on to the road surfaceignition means, etc. Also, the heating of the surface producesundesirable odors and/ or smoke as well as an ignition hazard whereexplosive mixtures of gas may be present (within access holes to sewers)or where inflammable material may be spilt on the road surface (petroletc.) which is thereby ignited, during heavy removal operationsinvolving a 3-6 inch depth. With concrete surfaces removal of the wornsurface is usually effected by a plurality of individually operatedpneumatic tools, which is time consuming and requires extensive laborcosts plus the necessity of one or more compressors and ancillaryequipment.

It is an object of the present invention to provide an improved roadworking machine for road surfaces which is capable of removing materialat a higher rate as compared to known designs.

According to the present invention, apparatus for removing a worn roadsurface down to a pre-determined depth prior to the application of a newsurface, comprises a chassis, support means for the chassis in the formof wheels or tracks located at the front and rear corners of thechassis, means to displace the chassis in a forward and/or reversedirection, a pick-carrying cutting device supported from the chassis andlocated within the support means thereof, and rotatable about ahorizontal axis at an angle to the longitudinal axis of the chassis, andmeans to adjust the cutting device in a substantially vertical plane todetermine the depth of road surface to be removed.

Preferably, the cutting device may take the form of a drum which isdriven by hydraulic means and the drum may be driven in the samedirection as the road wheels or tracks.

The drum is built up from one or more drum sections with each section,e.g. being 2 or 2'6 long thereby permitting one to select the number ofdrum sections best suited for the particular requirements. Accordinglyit may be desirable to mount a single drum section on the machine and toremove material eg up to approximately 6" depth (or whatever greater orlesser depth is required) over the 2' or 2'6" width of road covered bythe single drum section, or three drum sections could be mounted on themachine and material removed e.g. up to approximately 3" in depth overthe 8' or 10' width of road covered by the combined lengths of the drumsections. Of course, one could similarly mount two drum sections on themachine. When two or more drum sections are employed they may berotatable about a common axis which may be at right angles, or at someother angle, to the longitudinal axis of the chassis. Alternatively,they may be mounted in chelon with or without slight overlap of the endsof adjacent drum sections, and again at right angles or some otherangle, to the longitudinal axis of the chassis. Of course, it is notnecessary for the drum sections to be of the same length.

The chassis may be self-propelled or may be constituted as a trailer orsemi-trailer. With this latter arrangement the cutting device may beoperable and dis-placeable over a road width of, for example, 9 feet inwidth or over a third (or one lane) of the width of the road to beresurfaced so as to allow two thirds (or two lanes each 9 wide) of theroad to remain open for carrying trafiic, or one lane 9' wide where theroad is two lanes wide.

The hydraulic means for driving the cutting device may take the form ofone or more hydraulic motors which may be driven at variable speed andsupplied with pressure fluid from a chassis mounted pump driven by amain power source, which also serve to motivate the chassis.

With only a single drum section mounted on the chassis to give a deepcut, the chassis is advanced over the length of road surface, or portionthereof, which is to be removed. Then, if both picks and hydraulic meanspermit, the chassis may be moved laterally 2 or 2'6" and the cuttinghead driven in the reverse direction for a return cutting run of themachine. Alternatively, the chassis may flit back, with the cuttingdevice inoperative, to its original starting position ready for a secondcut.

It is possible, therefore, for the cutting device to project slightlylaterally beyond the chassis so that material may be removed over awidth greater than that of the chassis.

Preferably, each drum section has its peripheral picks mounted in asingle or multi-start helical form, such that the picks of the single oreach of helix will cut in sequence. Adjacent picks may be so spacedlaterally that their edges overlap one another for insuring attainmentof a smooth finished surface. Alternatively the lateral spacing ofadjacent picks may be increased. slightly so as not to overlap oneanother but to be slightly spaced from one another to produce a roughsurface, if improved bonding of the new surface is desired.

Preferably the picks are tipped with tungsten carbide. Advantageouslythey have two or more cutting edges so that even if reverse operation ofthe cutting head is not required. a pick can simply be reversed orrepositioned to present a fresh face when one of its cutting edgesbecomes worn.

Preferably conveyor means is associated with the chassis to remove thematerial detached by the picks, with loading means such as rotarypaddles also being provided to load the conveyor. If a front and rearsteer chassis is employed the detached material must pass under the rearof the chassis, whereas with four-wheel steer chassis, the latter mayadvance crabwise so that detached material does not pass under the rearof the chassis.

One suitable loading means consists of two inclined and horizontalploughs one at each side of the chassis and adapted to direct materialto the centre of the chassis wtih the distance of each plough from theroad being surface controllable. Any smaller material which passes underthe ploughs may be swept to the centre of the chassis by a brushrotatable about a horizontal axis paral lel to and behind each plough.

The conveyor means preferably consists of a conveyor itself mounted onthe chassis. Thus, a short conveyor of flat V form in side elevation mayhave one arm of the V extending under the chassis to a pick-up nose, andthe other arm extending upwardly away from the chassis and conveyorbeing pivoted to the rear of the chassis at the apex of the V with oneor a pair of hydraulic piston and cylinder units pivoted to the chassisand the other arm of the V so as to enable adjustment of the nose of theone arm to be adjusted with respect of the road surface.

To take account of camber of the road surface the chassis may be tiltedby elevating one side thereof. This may be effected by providing pairsof wheels at each side of the front and/or rear of the chassis which aremoveable relative to one another in a vertical sense, whereby one of thewheels of the pair may remain in contact with the road surface, whilethe other wheel is raised therefrom, thus elevating the chassis at thatpoint.

The invention will now be described in greater detail, by way ofexamples, shown in the accompany drawings, in which:

FIG. 1 is a side elevation of a machine according to the inventionprovided with two cutting drums and showing conveying apparatus.

FIG. 2 is a plan view of the machine of FIG. 1; and

FIG. 3 is a diagrammatic view of one of the drum sections.

In the drawings, the machine includes a chassis indicated at 1 having atthe corners of the chassis, front wheels 2A and rear wheels 2B restingon a road 3, at least two of which wheels are drivable and steerable andbetween which are supported two pick-carrying cutting devices 4, 5, onedisposed towards each side of the chassis. The machine has a drivers cab6 and a power unit 7.

Each cutting devices 4, is supported from the lower ends of two links 8,9, the upper ends of which are pivotally mounted on the chassis 1 bypins 10, 11. Two piston and cylinder units 12, 13 are each pivotallylocated respectively between brackets 14, 15 mounted on the chassis andbrackets 16, 17 mounted one on each link 8, the units 12 serving toadjust the position of each cutting device 4, 5, with respect to theroad. 3.

Each cutting device 4, 5 includes a single, or is made up of a pluralityof, drum sections, provided with picks 18 (FIG. 3) in pick boxes 19arranged in a helical manner around the drum periphery and driventhrough gearing housed in a casing 20 by a hydraulic motor 21 suppliedwith pressure fluid from a pump (not shown) driven by the power unit 7.Conveniently, the chassis is of a conventional type basically of Y shapein plan with the two arms of the Y adjacent a rear wheel 2B, and flatinverted V in side elevation, with the cutting devices 4, 5 locatedgenerally under the apex of the V, the location of the drivers cab 6providing good visual control.

Two inclined (FIG. 2) and horizontal (FIG. 1)

ploughs 22 one located at each side of the machine are adjustablysupported from a beam 23 which is pivoted at one end on a bracket 24depending from the chassis 1, the other end of each beam being securedto a hydraulic piston and cylinder unit 25.

A conveyor 26 is mounted on the chassis, and is of fiat V form in sideelevation having one arm 27 of the V extending under the chassis to apick-up nose 28, and the other arm 29 extending upwardly away from thechassis the conveyor being pivoted at 30 to the rear of the chassis witha pair of hydraulic piston and cylinder units 31 pivoted at 32 to thechassis and the arm 29 so as to enable adjustment of the nose 28 to beadjusted with respect of the road surface.

What I claim is:

1. Apparatus for removing a worn road surface down to a predetermineddepth prior to the application of a new surface, comprising a chassis,rotary support means mounting the chassis to enable it to be displacedin at least one direction longitudinally thereof, a cutting drumsupported by the chasses between the rotary support means and rotatableabout a horizontal axis at an angle to the longitudinal axis of thechassis, means for adjusting the cutting drum in a substantiallyvertical plane to set the depth of the road surface to be removed, drivemeans for rotating the drum, the drum being provided on its peripherywith a plurality of picks, each being substantially pointed at theirfree-end and presenting a flat cutting edge, so that, when said drum isto the road surface driving by said drive means, said cutting edges willcut away the road surface to said predetermined depth.

2. Apparatus as claimed in claim 1, wherein the drum is adapted to bedriven in the same direction of rotation as the rotary support means.

3. Apparatus as claimed in claim 2 including means to adjust the anglewhich the drum axis makes with the horizontal to thereby take intoaccount the camber of the road.

4. Apparatus for removing a worn road surface down to a predetermineddepth prior to the application of a new surface, comprising a chassis,rotary support means for the chassis to enable the chassis to bedisplaced in at least one direction longitudinally thereof, apick-carrying cutting device supported from the chassis and locatedbetween the support means and rotatable about a horizontal axis at anangle to the longitudinal axis of the chassis, means to adjust thecutting device in a substantially vertical plane to determine the depthof the road surface to be removed, conveyor means associated with thechassis for removing material detached by the cutting device, and meansfor loading the conveyor means comprising a horizontal plough at eachside of the chassis, the ploughs converging rearwardly so as to directmat rial to the center of the chassis, the distance of each plough fromthe road surface being controllable.

5. Apparatus for removing a worn road surface to a predetermined depthprior to the application of a new surface comprising a chassis, rotarysupport means for the chassis to enable the chassis to be displaced inat least one direction longitudinally thereof, at least onepick-carrying cutting device supported from the chassis and locatedbetween the support means and rotatable about a horizontal axis at anangle to the longitudinal axis of the chassis means for adjusting thecutting device in a substantially vertical plane to determine the depthof the road surface to be removed, a conveyor associated with thechassis to remove the material detached by the cutting device, andloading means to load the conveyor, said conveyor being composed of twoarms which meet each other in a fiat V-form when viewed in sideelevation, one of said arms extending under the chassis and having apick-up nose at its end, the other of said arms extending upwardly awayfrom the chassis the conveyor being pivoted to the rear of the chassisadjacent the apex of the V, the pick-up nose being adjustable withrespect to the road surface, by a pair of hydraulic piston and cylinderunits pivoted to the chassis and the other of the said arms.

6 2/1959 Bjorkrnan et a1. 29939X 1/1963 McDarrah 29939 9/1967 Whittaker29989 US. Cl. X.R.

